After he won the 1st set vs Borvanov and missed three breakpoints to go 3-0 up in the 2nd set (had 0-2 and 0/40 on Borvanov's serve), he was break points down in every service game. That was because Borvanov improved his level drastically after coming back from 0/40 in that game. Three times he saved break points by serve & volleying on second serve and finishing with volley winners. Of course, it was only Borvanov, but for the South African it was a very decent win. He even managed to break again in the end to win 6:4, 6:3.